Actually known and applied processes for decontamination of radioactive waste waters and for cleaning of waters in general are usually based on the application of sorption, precipitation or coprecipitation methods. In the first case a number of sorbents are used, operating for instance on principles of ion exchange (synthetic ion exchange material, material of natural, inorganic or organic origin), of adsorption, deposition on ion precipitates and similar in the second case there is a chemical precipitation of macro - impurities, or if trace radioactive material has to be eliminated - a coprecipitation, cocrystallization, creation of amorphous crystals and similar. An advantage of sorption methods is above all the possibility of regeneration or activation of most sorbents, using a relatively simple technology and apparatus with a generally favorable economy of the process. Coprecipitation methods are with respect to sorption processes more effective, mainly so far as decontamination from trace impurities is concerned. The requirement of supply of components of the carrier precipitates up to surpassing the corresponding solubility products and separation of the originating solid phases from the decontaminated water, makes however the precipitating and coprecipitating processes in a number of cases technically and economically less attractive.